Question

The local shelfer

d of their dogs and cats in
preparation for the holidays. The sale
was $ 100 for a dog and $15 for a
cat. If the shelter earned $1,390 for
seling dl 19 of their animds, how many
dogs and cats were adopted?

Answer 1

d + c = 19

100d + 15c = 1390

we can simplify the second equation

20d + 3c = 278

now d + c = 19

c = 19 - d

3c = 57 - 3d

now plug into second equation

20d + 57 - 3d = 278

17d = 278 - 57

17d = 221

d = 221 / 17

d = 13

now we can plug this into the first equation

13 + c = 19

c = 19 - 13

c = 6

13 dogs were sold and 6 cats were sold